1. Field of the Invention
The present invention relates generally to a wireless telephone, and in particular, to a wireless telephone using at least two speakers.
2. Description of the Related Art
FIG. 1 is a block diagram illustrating an example of a conventional speaker apparatus in a wireless telephone. Referring to FIG. 1, when an input audio signal (not shown) comprises a telephone conversation signal, a control section 10 outputs the telephone conversation signal to a speaker 40 via a voice codec 21 in a data processing section 20. However, when the input audio signal is a multimedia signal, the control section 10 outputs the multimedia signal to the speaker 40 via a multimedia codec 22 in the data processing section 20. The data processing section 20 includes the voice codec 21 for processing a telephone conversation signal and the multimedia codec 22 for processing a multimedia signal comprising a message reception alert tone or a ringing tone.
In an early version of the wireless telephone, a small voice-only speaker was used to generate a buzzer tone which provided a ringing tone or a variety of reception alert tones. Since the introduction of a melody Integrated Circuit (IC), also known as a YAMA chip, a large-sized speaker capable of supporting a polyphonic sound has been widely used. Recently, a composite speaker capable of outputting both voice and a variety of signaling tones is now generally employed. However, the composite speaker is relatively larger than a normal speaker. Therefore, when mounted on the front of a main printed circuit board in a wireless telephone, the composite speaker causes the wireless telephone to be thicker due to insufficient space in the wireless telephone's front casing. In contrast, when the composite speaker is mounted on the rear of the main printed circuit board, a space for mounting the composite speaker can be sufficiently secured. In this case, however, voice is barely delivered to a speaker in the front casing of the wireless telephone, thus failing to provide a good telephone conversation environment. In addition, in order to generate a variety of sounds, a separate speaker for outputting a signaling tone which is not voice must become larger in size as the number of polyphonic levels is increased. Also, the size of a speaker mounted on an upper portion of a Liquid Crystal Display (LCD) considerably affects the total size of the wireless telephone by decreasing the portability of the wireless telephone. Moreover, a future camcoder phone will have reduced speaker mounting space as compared with an existing wireless telephone of the same size due to the camcorder phone's mechanical structure for providing a rotary function of a camcoder.